Question Three [Total: 15 Marks] A jaw crusher crushes a solid material such that the average particle size is reduced from 35 mm to 5 mm, with the energy consumption of 13.0 kW/(kg/s). What will be the energy consumption needed to crush the same material of average size 50 mm to average size of 10 mm; (5) song do a) Assuming Rittinger's Law applies? b) Assuming Kick's Law applies? c) Which of these results would be regarded as being more reliable and why? (5) (5) Question Four [Total: 25 Marks] The size distribution of a dust as measured by a microscope is as follows. Particle Size (um) 0-2 2-4 4-8 8-12 12-16 16-20 20-24 Number of particles in range (-) 2000 600 140 40 15 5 2 Convert these data to obtain the distribution on a mass basis, and calculate the specific surface, assuming spherical particles of density 2650 kg/m